Page 114 - Miracle in the Eye

M MIRACLE IN THE EYE

In order to do all this, the spider needs not only an advanced visual system,
but an information processing center to make all the necessary calculations.
Jumping spiders have four pairs of eyes, for a total of eight. The front
two are the most impressive, perhaps the best eyes one can find in any
arthropod. The retina inside the eye can move in three dimensions, enabling
the spider to look in all directions and focus on its subject. The other six eyes
are positioned around the head, affording 360-degree vision. 43
The jumping spider's visual acuity is actually very similar to our own,
such that they even perceive images on a television screen. When most ani-
mals look at a television, they see only a series of moving dots. But research
has indicated that jumping spiders respond to televised pictures of other
spiders and insects.
The jumping spider's visual system is highly complex and, in some re-
spects, surpasses even a human's. A tiny spider can look in different direc-

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